I’m one of those users for who offline capability is an absolute must have. And since I kinda started this whole thing, I think my requirements matter a lot 
Why I need offline (or sync) mode: while in theory Internet connectivity is prevalent, in reality it’s not, and this is especially relevant in the mobile use case. I’m sometimes in mobile dead zones, in trains, on mountains. I need access to my content, it’s a hard requirement for me.
This particular conversation has been superseded by this: Real talk: SilverBullet 2.0 - #36 by zef
Whereas before I thought “it would be nice” to just have one mode to support, I’ve since figured out, doing so is a key factor to keep myself sane. Therefore, from v2, sync mode will be the primary option. I’m contemplating still adding a lite online mode, with all the fancy features (that require all content to be synced) disabled, for those who don’t want to sync their entire content database locally to a particular device.